In vehicles with enhanced starter motor technology, for example, micro hybrid vehicles, the engine is automatically stopped and restarted by a control system under certain conditions—e.g., when the vehicle is stopped. One type of start-stop system for a vehicle with an automatic transmission is a “Stop-in-Drive” system (SID). In such a system, the engine will only be autostopped when the transmission gear lever is in the “DRIVE” position. The engine is restarted when the gear lever is moved out of DRIVE.
In certain situations, a driver may want to have the vehicle in “NEUTRAL” for a period of time and does not require the engine to be running. In a conventional SID system, however, the engine will be autostarted when the vehicle is shifted out of DRIVE. This may reduce one of the benefits of an automatic engine start-stop system, by unnecessarily starting the engine when it is not required. If the engine was autostopped with the vehicle in NEUTRAL, it may be desirable to restart the engine when the vehicle is shifted out of NEUTRAL; however, if the vehicle was autostopped while in DRIVE, the gear lever may be in NEUTRAL only on its way to the final destination of “PARK”. In such a case it would be more desirable to keep the engine from automatically restarting when the vehicle is shifted out of NEUTRAL.
Therefore, a need exists for a system and method to control an engine in a vehicle such that after being autostopped and the transmission gear lever is shifted out of NEUTRAL, the vehicle engine will be automatically restarted under certain conditions, but not others.